The present technology relates to a battery including a cathode, an anode, and a solid electrolyte layer and to a method of manufacturing the same.
In recent years, as various electronic apparatuses have been widely used, demand for batteries as electric power sources thereof have been rapidly expanded. Applications of the electronic apparatuses are not limited to small-sized applications such as a mobile phone and a notebook-size personal computer, and include a wide variety of applications to large-sized applications such as an electric vehicle.
As types of batteries, a primary battery capable of only discharge and a secondary battery capable of charge and discharge are known. Representative examples of the latter secondary battery may include a lithium ion secondary battery. In general, a battery includes a cathode, an anode, and a liquid electrolyte (an electrolytic solution). Both the cathode and the anode contain active materials capable of inserting and extracting an electrode reactant.
However, in the case where a battery using an electrolytic solution is used, degraded performance, a failure, or the like of an electronic apparatus may occur resulting from problems (such as liquid leakage) specific to the electrolytic solution. In particular, in the case where the lithium ion secondary battery having high energy density or the like is used, if short circuit (internal short circuit) occurs due to liquid leakage, ignition and/or the like may occur in some cases.
Therefore, in order to resolve the problems specific to the electrolytic solution, using a solid-state electrolyte (a solid electrolyte) instead of the electrolytic solution has been considered. One reason for this is that, in this case, liquid leakage does not occur, and therefore, degradation of battery performance and the like caused by corrosion are prevented. Another reason for this is that, in this case, depending on types of solid electrolytes, an electric potential window is larger than that in the case where an electrolytic solution is used, and therefore, energy density is increased. A battery using such a solid electrolyte is a battery in which a cathode and an anode are laminated with a layer (a solid electrolyte layer) containing a solid electrolyte in between, and is generally called a total solid battery.
For compositions of batteries using solid electrolytes, various considerations have been made. Specifically, using a sulfur-based material such as Li2S—P2S5 as a solid electrolyte has been proposed (for example, see Non-Patent Literature 1). Further, it has been proposed that an amorphous polyaniline compound be used as a solid electrolyte, an electrode active material and the solid electrolyte be mixed, and thereafter, the resultant mixture be heated and fired (for example, see Patent Literature 1). Furthermore, it has been proposed that upon forming an electrode or a solid electrolyte layer with the use of a sintering method, an amorphous oxide be used as an auxiliary agent for sintering (for example, see Patent Literature 2). In association therewith, it has been proposed that an electrode and a solid electrolyte layer be formed with the use of a green sheet method (for example, see Patent Literature 3).